Which diameter size is NOT used for FCAW electrodes?

• A. 0.030 inch
• B. 0.045 inch
• C. 0.062 inch
• D. 0.052 inch

Answer: (C)

FCAW electrode diameter is chosen to match the current range and the wire feed system you’re using. Smaller diameters need less current and feed more easily, which is why they’re common for a variety of thicknesses and positions. Larger diameters deposit more metal but require higher current and a stiffer, more robust feed system, which isn’t as practical with typical FCAW equipment.

Common FCAW sizes you’ll see are around 0.030, 0.045, and 0.052 inches because they balance current needs, deposition rate, and ease of feeding. A diameter of 0.062 inches is not typically used for FCAW electrodes because it pushes into a range that standard FCAW power supplies and gun/feed systems don’t handle reliably, making arc stability and feeding difficult.

So, the diameter that isn’t used for FCAW electrodes in this context is 0.062 inch. The other sizes listed are within the usual FCAW options.